During installation of an existing air conditioner, a pipe routing mode of a heat exchanger usually includes a liquid refrigerant heat exchange pipe and a gaseous refrigerant heat exchange pipe, and both the liquid refrigerant heat exchange pipe and the gaseous refrigerant heat exchange pipe are usually installed on the right side of the heat exchanger. However, during installation of the air conditioner, an installation mode adopting leftward pipe routing or rightward pipe routing probably exists according to user demands. An existing air conditioning heat exchanger only adopts a single pipe routing mode, and has the technical problem of inconvenient installation.